ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Chemistry  (43)
  • Atomic, Molecular and Optical Physics  (11)
  • Magnetism
  • 1980-1984  (54)
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 17 (1980), S. 651-671 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ab initio MO calculations, using both minimal (STO-3G) and extended (Roos-Siegbahn) basis sets are reported for the systems methanethiol-imidazole, methanethiol-imidazole-formaldehyde, and methanethiol-imidazole-formamide, which, together with a point-change representation of a long α-helix, form models for the active site of papain. It is shown that the large electric field exerted by the helix in the active-site region is responsible for the presence of the essential residues Cys 25 and His 159 in the form of an ion pair RS- ··· ImH+, which is crucial for a recently proposed mechanism for the catalytic action of the enzyme. Also, an explanation is given for the anomalies in measured pK values for these residues. Detailed studies on the (sub)systems show that minimal basis sets lack the flexibility necessary for describing the type of proton transfer involved. We conclude that α-helices are essential parts of enzymes and that they play a significant role in the catalytic process.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 22 (1980), S. 2031-2043 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Saccharomyces cerevisiae CBS 426 was grown aerobically in continuous culture with a mixture of glucose and ethanol as the carbon source. The flows of biomass, glucose, ethanol, oxygen, and carbon dioxide were measured. A model for growth with two substrates was derived. Application of this model to the above-mentioned system yielded values for YATP and P/O. The joint confidence regions for these parameters were calculated. The relevance to industrial production of bakers' yeast is discussed.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Weinheim [u.a.] : Wiley-Blackwell
    Materials and Corrosion/Werkstoffe und Korrosion 31 (1980), S. 866-869 
    ISSN: 0947-5117
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Wear-resistance of anti-corrosion coatings in hydraulic steel constructionsDIN 55 928 gives rules for the protection of steel structures from corrosion by organic and metallic coatings. The durability against abrasion of such coatings is classified in part 5, table 8, columns 9-11, of this DIN. A notice to these columns gives indication of an abrasion-machine developed by the Bundesanstalt für Wasserbau in Karlsruhe.Giving the best results, this machine for testing the mechanic durability was chosen out of a number of testing systems. The result is an abrasion value (Abriebwert).This value enables us to classify the coatings in accordance with their durability.The abrasion machine, its main dimensions and its working are described.
    Notes: In der Tabelle 8 des Teils 5 der DIN 55 928 - Korrosionsschutz von Stahlbauten durch Beschichtungen und Überzüge - wird in Spalte 9-11 die mechanische Beanspruchung der Beschichtungen klassifiziert und in einer Bemerkung dazu auf ein Prüfgerät hingewiesen, das bei der Bundesanstalt für Wasserbau in Karlsruhe entwickelt wurde.Das Prüfgerät ist das Ergebnis einer längeren Entwicklung; es ermöglicht die Angabe eines „Abriebwertes“ als Abstufung der Belastbarkeit von Beschichtungssystemen.Die Entwicklung des Prüfgerätes wird dargelegt und das Prüfgerät sowie der Prüfvorgang beschrieben.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Weinheim [u.a.] : Wiley-Blackwell
    Materials and Corrosion/Werkstoffe und Korrosion 33 (1982), S. 647-653 
    ISSN: 0947-5117
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Corrosion fatigue of plasmanitrided steelThe effect of plasma-nitriding of steel 34 CrAlMo 5 on corrosion fatigue has been investigated in cyclic torsion. The tests were conducted in air, tap water and artifical sea water. Crack initiation and propagation have been studied by means of metallographic and fractographic methods to identify the fatigue mechanisms.Main results may be summarized as follows: The fatigue strength increases by about 40% due to plasma-nitriding over that of nonnitrided steel when tested in air. Even in corrosion environment plasma-nitriding improves remarkably the fatigue strength. The torsional fatigue strength of plasmanitrided specimen is not affected by the presence of tap water. In artifical sea water the distinct fatigue limit disappears. However, the fatigue life of the plasmanitrided specimen increases by factor of 10 compared with that of non-nitrided specimen. The reasons for this improvement were discussed by considering the mechanical and metallurgical aspects of the problems.
    Notes: Das Schwingungsrißkorrosionsverhalten von plasmanitriertem Stahl 34 CrAlMo 5 wurde in Torsionswechselversuchen an Luft, in Leitungswasser und in künstlichem Meerwasser untersucht. Rißbildung und Rißausbreitung wurden mittels metallographischer und fraktographischer Untersuchungsmethoden analysiert. Die Ergebnisse lassen sich folgendermaßen zusammenfassen: Durch das Plasmanitrieren wird an Luft eine Steigerung der Dauerfestigkeit um 40% gegenüber dem unbehandelten Zustand erreicht. Auch bei Einwirkung eines korrosiven Mediums bewirkt die Plasmanitrierschicht eine wesentliche Verbesserung des Dauerschwingverhaltens. Die Torsionswechselfestigkeit des plasmanitrierten Werkstoffes wird von einer Leitungswasserumgebung nicht beeinträchtigt. Im künstlichen Meerwasser existiert sowohl im unbehandelten als auch im plasmanitrierten Werkstoffzustand keine Dauerfestigkeit. Die Lebensdauer des plasmanitrierten Werkstoffes ist jedoch um eine Zehnerpotenz größer als die des unbehandelten Werkstoffes. Für die dargestellten Versuchsergebnisse werden verschiedene Deutungsmöglichkeiten diskutiert.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 18 (1980), S. 575-582 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This paper outlines a model for calculating the localized states of a 〈 100 〈 edge dislocation in α-Fe. The model used for the calculations is based on the multiple-scattering model (SCF-X α-SW). The purpose of this research is twofold: (1) To determine changes in electronic structure of the lattice near the core region of defects in α-Fe. (2) The variations of hydrostatic pressure about an edge dislocation produce a rearrangement of the conduction electrons. The question is what electrical interaction might be expected between a dislocation and a charged solute atom. The calculations show that the electrons tend to flow away from the compression side toward the dilated regions. The electrical contribution to the binding energy of a solute atom and a dislocation in α-Fe is of the order of 0.01 Ry/electronic unit charge of the atom.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 21 (1982), S. 711-716 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method within the PCILO framework for the study of periodic molecular systems involving impurities is described regarding a one-dimensional chain. The calculation of the whole system is reduced to the calculation of subsystem pairs only. By use of the first-neighbor approximation only one or two subsystem pairs must be considered for subsystems with identical or differing surroundings, respectively. The procedure described yields the ground state energies and charge distributions of the subsystems.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 23 (1983), S. 1091-1100 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The quantum dynamical behavior of the Van der Waals molecule (N2)2 and that of the ordered α and γ phases of solid N2 have recently been calculated, starting from the same ab initio N2—N2 potential. By interpreting the results of these calculations we try to improve our understanding of the libration/internal rotation motions of the N2 monomers and the orientational order-disorder (α-β) phase transition. Some new results are presented and further (mean-field and libron-model) calculations are proposed which assess explicitly the intermolecular pair correlation effects caused by the anisotropic interaction potential.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 25 (1984), S. 1055-1060 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The CNDO/BW modification of the CNDO/2 approximation was used within the PCILO framework. It was shown on some significant examples that all the good results of the original PCILO-CNDO/2 method can be reproduced by the modified version PCILO-CNDO/BW at least. Thus, preserving the quality of its results a computer-expense-reduced PCILO method is proposed for calculations on large molecular systems.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 25 (1984), S. 1061-1067 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The energetic behavior of one-dimensional (HF)n and (H2O)n chains with added or inserted H2O or HF was studied by means of the PCILOPSI method presented in Part I. The results were compared with the ones by the original PCILO method. The stabilization energies are in good qualitative agreement; energy differences due to impurity effects even quantitatively agree. The results show that the PCILOPSI method is well suited for the study of perturbed periodic molecular systems.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 19 (1981), S. 113-130 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Semilocal pseudopotentials have been determined for first-row (Li to Ne), second row (Na to Ar), and third-row atoms (K, Ca). Core-valence correlation is included by adjusting the pseudopotentials to experimental energies of ions with a single valence electron. Correlation within the valence shell is taken into account by using the spin-density functional formalism. The approximations involved in this approach are tested for atomic ionization energies as well as binding energies of monohydrides and alkali diatomics, agreement with experiment is usually satisfactory, but in certain applications density functionals should be already included in the fitting of the local part of the pseudopotential. In addition, 3s/3p and 3s/2p basis sets (for first and second row, respectively), designed for use in connection with our pseudopotentials, are given; it is shown that they yield reasonable results for both SCF and correlation energies.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...